Department of Animal Science, Cornell University, Ithaca, NY 14853, USA.
J Dairy Sci. 2012 Nov;95(11):6563-70. doi: 10.3168/jds.2011-5018. Epub 2012 Aug 23.
Ferulic acid (FRA), a phenolic compound with antioxidant and anticancer activities, naturally occurs in plants as a lignin precursor. Many veins of research have been devoted to releasing FRA from the lignin complex to improve digestibility of ruminant feeds. Thus, the objective of this research was to investigate the transfer of a given dosage of the free form of FRA into the milk of dairy cattle. Six mid- to late-lactation Holstein cows at the Cornell Research Farm (Harford, NY) were given 14-d adaptation to diet and stall position. Ad libitum access to a total mixed ration based on haylage and maize silage (31.1% neutral detergent fiber containing 5.52 mg of FRA/g) was provided during the study. A crossover design was implemented so that each cow alternated weekly between FRA-dosed and control. On d 1, jugular cannulas and urine catheters were placed in all cows. On d 2, FRA-dosed cows received a single dosage of 150 g of pure FRA powder at 0830 h via their fistula (n=4) or a balling gun for nonfistulated cows (n=2). Plasma, urine, feces, feed, orts, milk, and rumen fluid were sampled intensively for the next 36 h and analyzed for FRA concentration. On d 8, the cows crossed over and the experiment was repeated. When compared with the control, FRA administration did not have an effect on dry matter intake, milk yield, milk fat yield, milk protein yield, somatic cell count, or neutral detergent fiber content of orts and feces. The concentration of FRA in the feces did not change as a result of FRA dosage. As expected, FRA concentration increased dramatically upon FRA dosage and decreased over time until returning to basal levels in rumen fluid (4 h after dosage), plasma (5.5 h after dosage), urine (10 h after dosage), and milk (14 h after dosage). Baseline values for FRA in urine and rumen fluid were variable among cows and had an effect on FRA concentration in FRA-dosed cows. From this study, it is observed that orally ingested FRA can be transported into the milk and that the physiological transfer of FRA occurs from rumen to milk within 6.5 h or the first milking after dosage. Ferulic acid may affect the functionality of milk due to its antioxidant, anticancer, and antibacterial activities. Future research will be required to elucidate whether FRA in milk is bioavailable and bioactive, and to evaluate the complete sensory and microbiological effects of increased FRA and FRA degradation products in milk.
阿魏酸（FRA）是一种具有抗氧化和抗癌活性的酚类化合物，天然存在于植物中，是木质素的前体。许多研究都致力于将 FRA 从木质素复合物中释放出来，以提高反刍动物饲料的消化率。因此，本研究的目的是研究将一定剂量的游离形式的 FRA 转移到奶牛的牛奶中。康奈尔研究农场（纽约州哈福德）的 6 头处于泌乳中期至晚期的荷斯坦奶牛经过 14 天的适应期，适应饮食和畜栏位置。在研究期间，它们可以自由采食以干草和玉米青贮（中性洗涤剂纤维含量为 31.1%，含有 5.52 毫克 FRA/g）为基础的全混合日粮。采用交叉设计，使每头奶牛每周在 FRA 剂量组和对照组之间交替。在第 1 天，所有奶牛都放置了颈静脉插管和尿液导管。在第 2 天，FRA 剂量组奶牛在 0830 时通过瘘管（n=4）或球囊枪（非瘘管奶牛 n=2）接受 150 g 纯 FRA 粉末的单次剂量。在接下来的 36 小时内，密集采集血浆、尿液、粪便、饲料、剩料、牛奶和瘤胃液进行 FRA 浓度分析。在第 8 天，奶牛交叉并重复实验。与对照组相比，FRA 给药不会影响干物质摄入量、产奶量、乳脂产量、乳蛋白产量、体细胞计数或剩料和粪便的中性洗涤剂纤维含量。由于 FRA 剂量，粪便中 FRA 的浓度没有变化。正如预期的那样，FRA 剂量后 FRA 浓度急剧增加，随着时间的推移逐渐降低，直到在瘤胃液（剂量后 4 小时）、血浆（剂量后 5.5 小时）、尿液（剂量后 10 小时）和牛奶（剂量后 14 小时）中恢复到基础水平。尿液和瘤胃液中 FRA 的基线值在奶牛之间是可变的，并且对 FRA 剂量组中 FRA 浓度有影响。从这项研究中可以看出，口服摄入的 FRA 可以转移到牛奶中，并且 FRA 从瘤胃到牛奶的生理转移在剂量后 6.5 小时或第一次挤奶时发生。阿魏酸由于其抗氧化、抗癌和抗菌活性，可能会影响牛奶的功能。需要进一步研究以阐明牛奶中的 FRA 是否具有生物利用度和生物活性，并评估牛奶中 FRA 增加和 FRA 降解产物的完整感官和微生物学影响。
